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🇺🇸 Weather in San Francisco in January
This is what the weather in San Francisco (California, USA) was like in January over the years 2017–2026.
Key facts at a glance
Prevailing weather: Partly cloudy
Avg. daytime high
14.0 °C
11.8 °C – 14.8 °C
Avg. night-time low
7.0 °C
5.5 °C – 8.3 °C
Avg. rain days in period
9.5
31 % of days · ≥ 1.0 mm
Avg. precipitation in period
121 mm
8.4 mm – 303 mm
Avg. cloud cover
60 %
This data source has no sunshine hours – average cloud cover is shown instead.
Avg. sea temperature
13.3 °C
Sea temperature available for 1 of 10 years.
Extremes: Highest temperature 22.2 °C (17 Jan 2021) · Lowest temperature -0.5 °C (6 Jan 2017) · Avg. daily peak wind 18 km/h
Weather mix of all days
- 64Sunny
- 82Partly cloudy
- 69Cloudy
- 32Light rain
- 62Rain
- 1Snow
Summary
- On average 14.0 °C during the day and 7.0 °C at night.
- On average 9.5 rain days (Rain day = at least 1.0 mm of precipitation) with 121 mm of precipitation in total.
- The sea averaged 13.3 °C.
- Prevailing weather: Partly cloudy.
- Warmest year: 2026 (avg. 14.8 °C), coolest: 2017 (avg. 11.8 °C).
- Wettest year: 2017 (303 mm), driest: 2022 (8.4 mm).
- Extremes: 22.2 °C on 17 Jan 2021 and -0.5 °C on 6 Jan 2017.
Overall values from all 10 years. How is this calculated?
Charts
Temperatures per year
Average over your travel period
Avg. daytime high: 2017 12°, 2018 14°, 2019 14°, 2020 14°, 2021 15°, 2022 15°, 2023 13°, 2024 14°, 2025 14°, 2026 15°. Avg. night-time low: 2017 5°, 2018 8°, 2019 8°, 2020 7°, 2021 7°, 2022 6°, 2023 7°, 2024 8°, 2025 6°, 2026 7°. Sea temperature: 2017 –, 2018 –, 2019 –, 2020 –, 2021 –, 2022 –, 2023 –, 2024 –, 2025 –, 2026 13°.
Precipitation & rain days
Precipitation (mm): 2017 303, 2018 133, 2019 145, 2020 46, 2021 80, 2022 8, 2023 247, 2024 149, 2025 15, 2026 83.
Year by year
2026
Avg. max14.8°Avg. min7.1°- Rain days
- 7 Rain days
- Precipitation
- 82.7 mm
- Avg. cloud cover
- 55 % cloudy
- Sea temperature
- 13.3 °C
Max 17.2 °C · Min 3.1 °C
2025
Avg. max14.3°Avg. min6.1°- Rain days
- 2 Rain days
- Precipitation
- 14.5 mm
- Avg. cloud cover
- 37 % cloudy
- Sea temperature
- –
Max 17.5 °C · Min 3.3 °C
2024
Avg. max14.4°Avg. min8.3°- Rain days
- 15 Rain days
- Precipitation
- 149 mm
- Avg. cloud cover
- 68 % cloudy
- Sea temperature
- –
Max 19.6 °C · Min 3.9 °C
2023
Avg. max12.9°Avg. min6.8°- Rain days
- 13 Rain days
- Precipitation
- 247 mm
- Avg. cloud cover
- 55 % cloudy
- Sea temperature
- –
Max 15.9 °C · Min 1.6 °C
2022
Avg. max14.5°Avg. min6.3°- Rain days
- 3 Rain days
- Precipitation
- 8.4 mm
- Avg. cloud cover
- 52 % cloudy
- Sea temperature
- –
Max 16.6 °C · Min 0.8 °C
2021
Avg. max14.6°Avg. min7.2°- Rain days
- 8 Rain days
- Precipitation
- 80.2 mm
- Avg. cloud cover
- 61 % cloudy
- Sea temperature
- –
Max 22.2 °C · Min 2.7 °C
2020
Avg. max13.7°Avg. min7.1°- Rain days
- 6 Rain days
- Precipitation
- 45.6 mm
- Avg. cloud cover
- 64 % cloudy
- Sea temperature
- –
Max 18.7 °C · Min 4.5 °C
2019
Avg. max14.4°Avg. min7.9°- Rain days
- 12 Rain days
- Precipitation
- 145 mm
- Avg. cloud cover
- 69 % cloudy
- Sea temperature
- –
Max 17.7 °C · Min 2.5 °C
2018
Avg. max14.4°Avg. min8.0°- Rain days
- 12 Rain days
- Precipitation
- 133 mm
- Avg. cloud cover
- 71 % cloudy
- Sea temperature
- –
Max 18.3 °C · Min 4.5 °C
2017
Avg. max11.8°Avg. min5.5°- Rain days
- 17 Rain days
- Precipitation
- 303 mm
- Avg. cloud cover
- 68 % cloudy
- Sea temperature
- –
Max 14.6 °C · Min -0.5 °C
Frequently asked questions
- How warm is it in San Francisco in January?
- Daytime highs averaged 14.0 °C, night-time lows 7.0 °C. The highest value of the past 10 years was 22.2 °C (17 Jan 2021), the lowest -0.5 °C (6 Jan 2017).
- How often does it rain in San Francisco in January?
- On average there were 9.5 rain days (at least 1 mm) with 121 mm of precipitation in total.
- How warm is the sea in San Francisco in January?
- The sea temperature averaged 13.3 °C (open-sea point approx. 6 km from the town).
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Other destinations in January
Data sources
- Weather data
- Data obtained from the NASA Langley Research Center (LaRC) POWER Project funded through the NASA Earth Science/Applied Science Program
Reanalysis (weather model constrained by observations) on a coarse grid of about 50 km. Values represent a large area and can differ from local conditions, especially on islands, coasts and in mountains. Snow depth is the model value for the grid cell, not the depth on the slopes. No sunshine duration.
Reanalysis (weather model constrained by observations)
Reanalysis values represent a grid cell (approx. 25–50 km) and may differ from local measurements on coasts, islands and in mountains. - Sea temperature
- MUR SST data were provided by JPL under support by NASA MEaSUREs program; accessed via NOAA CoastWatch ERDDAP
Daily multi-scale ultra-high resolution (≈ 1 km) analysis of satellite measurements (infrared, microwave) and in-situ data. Represents the foundation temperature below the daily warm surface layer. (Satellite and in-situ analysis) - Sea measuring point approx. 6 km from the location (37.830, -122.450)
- Place search
- Natural Earth (public domain) · GeoNames (CC BY 4.0) / OpenStreetMap (ODbL)